To me it sounds like you got into just an unlucky and shitty group of people since from my personal exp, ive never seen an experience that bad before (Ive been playing this game since beta of vanilla, and ive seen my fair share of people and their stupidity in wow). In pvp people tend to be more harsher i find but from a pve perspective (i dont pvp all that often); i have heard people say negative things about a woman playing but very rarely. I have raided with a bunch of 25 man guilds that had a few female members while doing heroic content, and no one complained or said anything negative.
My best advice is to report them, and to prove them wrong. Back in BC i was a retribution paladin (ive always been) and at that time they wernt in the best shape and alot of people refused to take any ret to raids because they thought they had shit damage. So when i got some dumb ass telling me sorry but he wouldnt take me to a raid or invite me to a raiding guild because i was ret i would respond with: "i will be one of your top dps and live in 99% of boss fights". And then i would go into his raid and bust my ass to prove them wrong, and sure enough i would be one of the top (would even get whispered that they were sorry they doubted me). So if i was in your shoes i would of said: yes im a woman, and watch me destroy you and win this bg.
In short what im trying to say is people are stupid and they assume things without even giving someone a shot, they judge a book by its cover. Report dicks that whispered you, dont let it get you down and prove them wrong. Show them you are a good player, and make them eat their words when you destroy them in that bg by being the best dps, healer, flag caper or what ever you got to be to be the MVP of the team.